Micro electro mechanical system and manufacturing process thereof

Abstract

The invention relates to the field of micro-electro-mechanical systems, in particular to a micro-electro-mechanical system and a manufacturing process thereof. The micro-electro-mechanical system is provided with a pattern area and a cutting channel area which are adjacently arranged, and the micro-electro-mechanical system comprises a substrate, a plurality of alignment marks and a mark supporting structure, wherein the alignment marks and the mark supporting structure are formed in the cutting channel area. The mark supporting structure is supported on the substrate and used for supporting at least part of the alignment mark. The mark supporting structure comprises a suspension part and a plurality of supporting parts arranged on the edge of the suspension part, the multiple supporting parts are all supported on the cutting channel area of the substrate, the suspension part is supported on the supporting parts and suspended on the substrate, and the alignment mark is supported on the suspension part of the mark supporting structure. The mark supporting structure is used for supporting the alignment marks corresponding to the layers of the bridge leg structures on the upper portion, the alignment marks are prevented from scattering into the MEMS structure, the sacrificial layer and the substrate below the mark supporting structure are protected when the alignment marks are formed through etching, the quality of the MEMS can be improved, and the service life of the MEMS can be prolonged.

Description

Technical Field

[0001] The present invention relates to the field of micro-electromechanical systems, and in particular to a micro-electromechanical system and a manufacturing process thereof. Background Art

[0002] When preparing micro-electromechanical systems (MEMS) such as uncooled infrared detectors, it is necessary to form multiple alignment marks in the cutting area, and the alignment marks are used to ensure the accuracy of the etching position of the graphic area. The uncooled infrared detector includes a bridge leg structure, which includes a microbolometer and an anchor column at the top. The anchor column supports the microbolometer so that it is suspended from the bottom substrate, thereby improving the sensitivity and accuracy of the detection.

[0003] When preparing an uncooled infrared detector, it is necessary to deposit, etch and release the sacrificial layer, and finally form a cavity inside the uncooled infrared detector, so that the bottom of the microbolometer is suspended in the air to form a bridge leg structure. Since the alignment marks corresponding to the bridge leg structure are all formed above the sacrificial layer, after the sacrificial layer is released, some of the alignment marks are suspended in the air and are very likely to fall into the cavity, which will affect the reliability of the detector. Summary of the invention

[0004] The object of the present invention is to provide a non-cooled infrared detector, a mark support structure and a manufacturing process thereof which can prevent alignment marks from scattering.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A micro-electromechanical system having a graphic area and a cutting road area arranged adjacent to each other, and the micro-electromechanical system comprises:

[0007] substrate;

[0008] A plurality of alignment marks formed in the scribe line region;

[0009] A mark support structure is formed in the cutting path area, supported on the substrate, and used to support at least part of the alignment mark. The mark support structure includes a suspension portion and a plurality of support portions arranged at the edge of the suspension portion. The plurality of support portions are all supported on the cutting path area of ​​the substrate. The suspension portion is supported on the support portion and suspended on the substrate. The alignment mark is supported on the suspension portion of the mark support structure.

[0010] Optionally, the supporting portion has a first end and a second end opposite to the first end, the supporting portion is configured as a hollow columnar structure with the second end being open, the second end of the supporting portion is connected to the floating portion on a side close to the floating portion, and the first end of the supporting portion is closed and connected to the substrate, a stop layer is formed on the side of the floating portion away from the substrate, and the depth of any alignment mark is less than or equal to the depth of the bottom surface of the stop layer.

[0011] Optionally, the microelectromechanical system is an uncooled infrared detector, and the substrate includes an integrated circuit wafer, a reflective layer and a passivation layer stacked in sequence, a plurality of mutually separated reflective layers are arranged in the graphic area, and the passivation layer covers part of the integrated circuit wafer and the reflective layer.

[0012] Optionally, the uncooled infrared detector also includes a bridge leg structure formed in the graphic area, the bridge leg structure includes a first dielectric layer and a thermistor, the first dielectric layer includes a connecting portion, a longitudinal portion and a transverse portion, the connecting portion is directly connected to the surface of the passivation layer, the transverse portion is suspended on the substrate, the longitudinal portion is supported between the connecting portion and the transverse portion, and the thermistor is supported on the transverse portion.

[0013] Optionally, the uncooled infrared detector includes a support layer, a portion of the support layer corresponding to the graphic area is the first dielectric layer, and a portion of the support layer corresponding to the cutting path area is the mark support structure.

[0014] Optionally, the supporting layer is a silicon nitride layer.

[0015] Optionally, the passivation layer is a silicon oxide layer.

[0016] In a second aspect, the present invention further provides a manufacturing process of the above-mentioned micro-electromechanical system, comprising:

[0017] Depositing a sacrificial layer on the surface of the substrate;

[0018] Etching the sacrificial layer to form a plurality of deposition holes penetrating the sacrificial layer in the cutting path area, wherein the deposition holes are connected to the substrate;

[0019] Depositing a support layer, so that the cutting path area forms the mark support structure, the part of the mark support structure connected to the inner wall of the deposition hole and part of the surface of the substrate is the support part, and the part of the mark support structure connected to the surface of the sacrificial layer is the suspension part;

[0020] sequentially forming a plurality of layers including the alignment marks on the surface of the support layer;

[0021] The sacrificial layer is released.

[0022] Optionally, sequentially forming a plurality of layers including the alignment marks on the surface of the support layer comprises:

[0023] A thermosensitive layer is deposited on the surface of the support layer and etched to obtain a thermistor with a specific structure in the graphic area, and the thermosensitive layer is retained at a position corresponding to the suspended portion of the mark support structure in the cutting path area.

[0024] Optionally, the sacrificial layer is a polyimide layer.

[0025] According to the first aspect of the present invention, a mark support structure is formed in the cutting path area, and alignment marks corresponding to each layer of the bridge leg structure are formed above the mark support structure. Each alignment mark is supported by the mark support structure, thereby preventing the alignment mark from being scattered inside the structure of the MEMS, and protecting the sacrificial layer and substrate below the mark support structure when the alignment mark is formed by etching. A plurality of support parts surrounding the suspension part are provided, so that the mark support structure has a relatively stable structure and improves the support capacity.

[0026] Furthermore, the support portion is configured as a hollow column with a closed bottom and an open top, which is convenient for deposition on a sacrificial layer and has a strong support force. By setting a stop layer, the mark support structure is protected by the stop layer to prevent the etching depth required for the graphic area from being too deep when etching any layer, resulting in damage to the mark support structure due to etching.

[0027] Furthermore, multiple reflective layers are provided on the substrate of the uncooled infrared detector to cover part of the integrated circuit wafer, which helps to enhance the detector's absorption efficiency of infrared radiation. The passivation layer covers the reflective layer and the surface of the integrated circuit wafer, which helps to separate the integrated circuit wafer from the bridge leg structure and play a protective role.

[0028] Furthermore, by providing the first dielectric layer to support the thermistor, it helps to improve the structural stability of the uncooled infrared detector, reduce the risk of the thermistor falling off, and help improve the quality and life of the uncooled infrared detector.

[0029] Furthermore, the first dielectric layer and the marking support structure are formed at one time by depositing the support layer, which helps to simplify the preparation process.

[0030] According to the second aspect of the present invention, a sacrificial layer is formed on the surface of the substrate, and the sacrificial layer is etched to form a template of the shape required by the marking support structure, thereby forming a marking support structure of a specific shape, so that the marking support structure still has a stable structure and supporting force after the sacrificial layer is released, thereby suppressing the falling off of the alignment mark and protecting the structure of the MEMS.

[0031] Furthermore, by retaining the thermosensitive layer on the surface of the mark support structure, the mark support structure is protected when the alignment mark is formed by etching above the mark support structure, to prevent the mark support structure from being damaged during etching because the etching depth required in the graphic area is greater than the position depth of the mark support structure in the cutting area when the graphic area and the cutting area are etched simultaneously.

[0032] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a cross-sectional change diagram of the cutting path area of ​​the uncooled infrared detector shown in the first embodiment of the present invention during the manufacturing process;

[0034] Figure 2 A cross-sectional diagram of a graphic area of ​​an uncooled infrared detector during the manufacturing process shown in the first embodiment of the present invention;

[0035] Figure 3 This is a flowchart of the manufacturing process of the uncooled infrared detector shown in the first embodiment of the present invention;

[0036] Figure 4 It is a top view of the cutting path area of ​​the uncooled infrared detector in the first embodiment of the present invention.

[0037] Legend: 101-first alignment mark, 102-second alignment mark, 103-third alignment mark, 104-fourth alignment mark, 105-fifth alignment mark, 106-sixth alignment mark, 1-substrate, 11-integrated circuit wafer, 111-coupling capacitor, 12-reflective layer, 13-passivation layer, 2-sacrificial layer, 21-deposition hole, 22-sacrificial hole, 31-mark support structure, 311-suspension part, 312-support part, 32-first dielectric layer, 321-connecting part, 322-longitudinal part, 323-lateral part, 4-thermistor, 41-thermistor, 5-second dielectric layer, 6-third dielectric layer, 61-first contact hole, 62-second contact hole, 7-bridge leg metal layer, 8-anchor column metal layer, 9-fourth dielectric layer. DETAILED DESCRIPTION

[0038] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0040] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0042] See also Figure 1 and Figure 2 The micro-electromechanical system to be protected by the present invention has a graphic area and a cutting road area arranged adjacent to each other, and the micro-electromechanical system includes a substrate 1, and a plurality of alignment marks and a mark support structure 31 formed in the cutting road area. The mark support structure 31 is supported on the substrate 1 and is used to support at least part of the alignment mark. The mark support structure 31 includes a suspension portion 311 and a plurality of support portions 312 arranged at the edge of the suspension portion 311, and the plurality of support portions 312 are all supported on the cutting road area of ​​the substrate 1, the suspension portion 311 is supported on the support portion 312, and is suspended on the substrate 1, and the alignment mark is supported on the suspension portion 311 of the mark support structure 31.

[0043] A mark support structure 31 is formed in the cutting road area, and alignment marks corresponding to each layer of the bridge leg structure are formed above the mark support structure 31. The mark support structure 31 supports each alignment mark, thereby preventing the alignment mark from scattering inside the structure of the MEMS. When the alignment mark is formed by etching, the sacrificial layer 2 and the substrate 1 under the mark support structure 31 can be protected, which helps to improve the quality and life of the micro-electromechanical system. A plurality of support parts 312 surrounding the suspension part 311 are provided, so that the mark support structure 31 has a relatively stable structure and improves the support capacity.

[0044] Please refer to the following examples for details.

[0045] Embodiment 1:

[0046] See also Figure 1 , Figure 2 , Figure 3 and Figure 4 The manufacturing process of the uncooled infrared detector shown in a preferred embodiment of the present application includes:

[0047] S100 , depositing a sacrificial layer 2 on the surface of the substrate 1 .

[0048] S210 , etching the sacrificial layer 2 to form a plurality of deposition holes 21 penetrating the sacrificial layer 2 in the cutting path area, wherein the deposition holes 21 are connected to the substrate 1 .

[0049] S300, depositing a support layer to form a marking support structure 31 in the cutting path area, wherein the portion of the marking support structure 31 connected to the inner wall of the deposition hole 21 and a portion of the surface of the substrate 1 is the supporting portion 312, and the portion of the marking support structure 31 connected to the surface of the sacrificial layer 2 is the suspended portion 311.

[0050] S400, forming a plurality of layers with alignment marks on the surface of the support layer in sequence.

[0051] S500 , releasing the sacrificial layer 2 .

[0052] Before manufacturing the uncooled infrared detector, the graphics of multiple layers and the alignment marks therein are pre-designed in this embodiment. A rectangular marking area is set in the cutting area to centrally form multiple alignment marks. Alignment marks can be divided into two forms: "concave" and "convex". The concave mark represents that the film at the marking pattern is etched away, leaving a pit; the convex mark represents that the film at the marking pattern is retained, and the film outside the marking pattern is etched away, leaving a boss. The design content in this embodiment is shown in Table 1 below.

[0053] Table 1:

[0054]

[0055] In this embodiment, the layers are formed sequentially according to the above table, and corresponding patterns are formed in the pattern area of ​​each layer, and corresponding alignment marks are formed in the cutting path area of ​​this layer, so as to achieve alignment of the layers.

[0056] In step S100, the substrate 1 includes an integrated circuit wafer 11, a reflective layer 12 and a passivation layer 13 which are stacked in sequence. An integrated circuit is formed on one side surface of the integrated circuit wafer 11. According to the design pattern of the first layer, a plurality of reflective layers 12 separated from each other are formed in the pattern area on the surface of the integrated circuit wafer 11, and two alignment marks are formed in the cutting path area. The reflective layers 12 at both ends are connected to the circuit formed on the integrated circuit wafer 11 through coupling capacitors 111. The passivation layer 13 covers part of the integrated circuit wafer 11 and the reflective layer 12, and plays a role of isolation and protection. In this embodiment, the passivation layer 13 is a silicon oxide layer, and the sacrificial layer 2 is a polyimide layer.

[0057] While performing step S210, the following operations are also performed in the graphics area:

[0058] S220 , etching the sacrificial layer 2 to form a plurality of sacrificial holes 22 penetrating the sacrificial layer 2 in the pattern region, wherein the sacrificial holes 22 are connected to the substrate 1 .

[0059] In step S2, with the alignment mark formed in the first layer as a reference, a sacrificial hole 22 corresponding to the coupling capacitor 111 is etched in the graphic area according to the design pattern of the second layer, and a plurality of square-shaped deposition holes 21 are formed at the edge of the mark area in the cutting path area, and the plurality of deposition holes 21 form a rectangular shape.

[0060] In step S300, the support layer is a silicon nitride layer, and the support layer located in the graphic area forms a first dielectric layer 32. The portion of the first dielectric layer 32 connected to the inner wall of the sacrificial hole 22 is the longitudinal portion of the first dielectric layer 32, the portion connected to the surface of the passivation layer 13 is the connecting portion of the first dielectric layer 32, and the portion connected to the surface of the sacrificial layer 2 is the transverse portion of the first dielectric layer 32. The support portion 312 of the marking support structure 31 is formed on the inner wall of the box structure with the top opening surrounded by the deposition hole 21 and the upper surface of the passivation layer 13, the closed lower portion of the support portion 312 is the first end of the support portion 312, the open top of the support portion 312 is the second end of the support portion 312, and the second end of the support portion 312 is connected to the part of the support layer supported on the sacrificial layer 2 as a whole. A plurality of support portions 312 form a rectangular structure, and the support layer surrounding the plurality of support portions 312 is the suspension portion 311. At this time, the suspension portion 311 has a relatively stable structure and supporting capacity.

[0061] Step S400 includes:

[0062] S410, deposit the thermosensitive layer 4 and the second dielectric layer 5 on the surface of the support layer as a whole, and etch according to the design pattern of the third layer. A thermistor 41 of a specific structure is obtained in the graphic area, and only the part of the second dielectric layer 5 covering the thermistor 41 is retained. Since the unnecessary film layer is usually completely etched at the position corresponding to the cutting path area of ​​each layer, the thermosensitive layer 4 and the second dielectric layer 5 are completely removed in the cutting path area in the prior art. In the present application, only the thermosensitive layer 4 and the second dielectric layer 5 on the marking support structure 31 in the marking area are retained in the cutting path area, and the two together form a stop layer protecting the marking support structure 31. In the subsequent process flow of forming the indicator mark, the existence of the stop layer makes the effect difference when the part of the thermosensitive layer 4 and the second dielectric layer 5 that is not retained in the graphic area and the cutting path area is etched at the same time, which helps to protect the integrity of the marking support structure 31, and cooperates with the marking support structure 31 to protect the sacrificial layer 2, thereby avoiding the etching operation from penetrating into the sacrificial layer 2 and preventing the sacrificial layer from being exposed. A first alignment mark 101 is formed in the cutting path area, and the first alignment mark 101 penetrates the thermosensitive layer 4, and the bottom reaches the mark support structure 31. The first alignment mark 101 is located near the edge of the suspended portion 311 of the mark support structure 31. In this embodiment, the thermosensitive layer 4 is a vanadium oxide layer, and the second dielectric layer 5 is a silicon nitride layer.

[0063] S420, the third dielectric layer 6 is deposited as a whole to cover the thermistor 41, the second dielectric layer 5 and the support layer, and is etched according to the design pattern of the fourth layer. A first contact hole 61 is etched in the pattern area corresponding to the connection portion of the first dielectric layer 32 to connect the third dielectric layer 6 and the reflective layer 12, and a portion of the connection portion of the first dielectric layer 32 is retained. A second alignment mark 102 adjacent to the first alignment mark 101 is formed in the cutting path area, and the second alignment mark 102 penetrates the second dielectric layer 5, and the bottom is embedded in the thermosensitive layer 4. In this embodiment, the third dielectric layer 6 is a silicon nitride layer. Although the etching operation penetrates the third dielectric layer 6, the first dielectric layer 32 and the passivation layer 13 in the pattern area, the etching depth stops at the thermosensitive layer 4 in the cutting path area due to the protection of the stop layer, preventing the mark support structure 31 from being damaged or even corroded.

[0064] S430, etching is performed on the surface of the third dielectric layer 6 according to the design pattern of the fifth layer. Two symmetrical second contact holes 62 are formed in the pattern area corresponding to the position above the thermosensitive layer 4. The two second contact holes 62 penetrate the second dielectric layer 5, and the bottom reaches the thermistor 41, so that part of the surface of the thermistor 41 is exposed. A third alignment mark 103 is formed in the cutting path area. The third alignment mark 103 is located on the side of the second alignment mark 102 away from the first alignment mark 101, and the third alignment mark 103 penetrates the second dielectric layer 5, and the bottom reaches the top of the thermosensitive layer 4, which is slightly shallower than the second alignment mark 102.

[0065] S440, depositing a bridge leg metal layer 7 on the third dielectric layer 6 to cover the third dielectric layer 6, the first contact hole 61 and the second contact hole 62. In this embodiment, the bridge leg metal layer 7 is a titanium layer, and directly contacts the thermistor 41 and the reflective layer 12 connected to the coupling capacitor 111; the anchor column metal layer 8 is aluminum copper.

[0066] S450, etching is performed on the surface of the anchor metal layer 8 according to the design pattern of the sixth layer. An anchor metal layer 8 for strengthening the structure is formed at the position corresponding to the first contact hole 61 in the pattern area, and an anchor metal layer 8 covering a portion of the bridge leg metal layer 7 is formed on the side of the third alignment mark 103 in the cutting track area away from the second alignment mark 102, forming a fourth alignment mark 104. In this embodiment, the anchor metal layer 8 is an aluminum layer.

[0067] S460, the surface of the bridge leg metal layer 7 is etched according to the design pattern of the seventh layer. In the pattern area, the part of the bridge leg metal layer 7 between the two second contact holes 62 is etched to expose the third dielectric layer 6. At this time, the part of the bridge leg metal layer 7 between the two second contact holes 62 forms a short circuit, so that the current only passes through the thermistor 41. The bridge leg metal layer 7 is etched in the cutting area, so that the bridge leg metal layer 7 only retains an area on the side of the anchor column metal layer 8 away from the third alignment mark 103, forming a fifth alignment mark 105.

[0068] S470, the fourth dielectric layer 9 is deposited as a whole to protect the exposed bridge leg metal layer 7 and anchor column metal layer 8, and is etched according to the design pattern of the eighth layer. In the graphic area, the first dielectric layer 32, the third dielectric layer 6, the bridge leg metal layer 7 and the fourth dielectric layer 9 are etched through, so that the bridge leg structure is formed into a specific shape. The sixth alignment mark 106 is etched on the side of the fifth alignment mark 105 away from the fourth alignment mark 104. The sixth alignment mark 106 penetrates the first thermosensitive layer 4, and the bottom reaches the first dielectric layer 32. In other embodiments, the sixth alignment mark 106 can be etched only to the thermosensitive layer 4 or partially etched to the first dielectric layer 32. The etching operation in this step will penetrate the first dielectric layer 32, the third dielectric layer 6, the bridge leg metal layer 7 and the fourth dielectric layer 9 in the graphic area and stop on the sacrificial layer 2. In the cutting path mark area, a stop layer, i.e., the thermal-sensitive layer 4 and the second dielectric layer 5, is provided so that the film at the position to be etched to form the sixth alignment mark 106 is thicker than the position to be etched in the graphic area, thereby preventing the etching depth of the cutting path area from being too large when the etching penetrates the first dielectric layer 32 according to the requirements of the graphic area, thereby damaging the mark support structure 31, thereby protecting the mark support structure 31.

[0069] In step S410, since the thermistor 4 and the sacrificial layer 2 are isolated by the support layer, the structure of the sacrificial layer 2 is prevented from being damaged during etching, which helps to maintain the support force of the sacrificial layer 2 before the uncooled infrared detector is prepared, and prevents the collapse and deformation of the structure during the preparation process. In step S420, the side wall of the thermistor 41 is protected by the third dielectric layer 6, and through steps S420, S430 and S440, the bridge leg metal layer 7 is used to form a circuit connecting the thermistor 41 and the integrated circuit wafer 11. In step S460, since the fourth alignment mark 104 formed in step S450 covers part of the bridge leg metal layer 7, and the anchor column metal layer 8 is not etched in step S460, the bridge leg metal layer 7 covered by the fourth alignment mark 104 is retained, and at this time, the height of the fourth alignment mark 104 is higher than the fifth alignment mark 105. In step S470 , the depth of the sixth alignment mark 106 is the same as the initial depth of the first alignment mark 101 . Since the first alignment mark 101 is deposited multiple times at the bottom in subsequent processes, the depth of the sixth alignment mark 106 is smaller than the first alignment mark 101 , thereby avoiding penetrating into the sacrificial layer structure 2 .

[0070] In step S400 , the positions of the plurality of alignment marks all correspond to the suspended portion 311 of the mark support structure 31 , and the arrangement direction is parallel to the long side of the suspended portion 311 of the mark support structure 31 .

[0071] In step S500, the sacrificial layer 2 is released, and the suspended portion 311 of the mark support structure 31 is in a suspended state. Since the multiple alignment marks are supported by the suspended portion 311 of the mark support structure 31 instead of being directly suspended in the air, the multiple alignment marks are supported by the mark support structure 31, thereby preventing the alignment marks from falling into the interior of the uncooled infrared detector.

[0072] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0073] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims.

Claims

1. A micro-electromechanical system, characterized in that: A micro-electromechanical system having a graphic area and a cutting road area arranged adjacent to each other includes: base(1); A plurality of alignment marks formed in the scribe line region; A mark support structure (31) is formed in the cutting path area, supported on the substrate (1), and used to support at least part of the alignment mark. The mark support structure (31) includes a suspension portion (311) and a plurality of support portions (312) arranged at the edge of the suspension portion (311). The plurality of support portions (312) are all supported on the cutting path area of ​​the substrate (1). The suspension portion (311) is supported on the support portion (312) and is suspended on the substrate (1). The alignment mark is supported on the suspension portion (311) of the mark support structure (31).

2. The micro-electromechanical system according to claim 1, characterized in that: The support portion (312) has a first end and a second end that are arranged opposite to each other. The support portion (312) is configured as a hollow columnar structure with an opening at the second end. The second end of the support portion (312) is connected to the suspension portion (311) at a side close to the suspension portion (311), and the first end of the support portion (312) is a closed structure connected to the substrate (1). A stop layer is formed on a side of the suspension portion (311) away from the substrate, and the depth of any alignment mark is less than or equal to the depth of the bottom surface of the stop layer.

3. The micro-electromechanical system according to claim 1 or 2, characterized in that: The micro-electromechanical system is an uncooled infrared detector, and the substrate (1) comprises an integrated circuit wafer (11), a reflective layer (12) and a passivation layer (13) which are stacked in sequence, a plurality of mutually separated reflective layers (12) are all arranged in the graphic area, and the passivation layer (13) covers a portion of the integrated circuit wafer (11) and the reflective layer (12).

4. The micro-electromechanical system according to claim 3, characterized in that: It also includes a bridge leg structure formed in the graphic area, the bridge leg structure includes a first dielectric layer (32) and a thermistor, the first dielectric layer (32) includes a connecting portion, a longitudinal portion and a transverse portion, the connecting portion is directly connected to the surface of the passivation layer (13), the transverse portion is suspended on the substrate (1), the longitudinal portion is supported between the connecting portion and the transverse portion, and the thermistor is supported on the transverse portion.

5. The micro-electromechanical system according to claim 4, characterized in that: It comprises a support layer, wherein the portion of the support layer corresponding to the graphic area is the first dielectric layer (32), and the portion of the support layer corresponding to the cutting track area is the mark support structure (31).

6. The micro-electromechanical system according to claim 5, characterized in that: The supporting layer is a silicon nitride layer.

7. The micro-electromechanical system according to claim 3, characterized in that: The passivation layer (13) is a silicon oxide layer.

8. A manufacturing process of a micro-electromechanical system according to any one of claims 1 to 7, characterized in that: include: Depositing a sacrificial layer (2) on the surface of the substrate (1); Etching the sacrificial layer (2) to form a plurality of deposition holes (21) penetrating the sacrificial layer (2) in the cutting path area, wherein the deposition holes (21) are connected to the substrate (1); Depositing a support layer so that the cutting path area forms the mark support structure (31), the portion of the mark support structure (31) connected to the inner wall of the deposition hole (21) and a portion of the surface of the substrate (1) is the support portion (312), and the portion of the mark support structure (31) connected to the surface of the sacrificial layer (2) is the suspension portion (311); sequentially forming a plurality of layers including alignment marks on the surface of the support layer; The sacrificial layer (2) is released.

9. The manufacturing process according to claim 8, characterized in that Sequentially forming a plurality of layers including alignment marks on the surface of the support layer comprises: A thermosensitive layer (4) is deposited on the surface of the support layer and etched to obtain a thermistor (41) of a specific structure in the graphic area, and the thermosensitive layer (4) is retained at a position corresponding to the suspended portion (311) of the marking support structure (31) in the cutting path area.

10. The manufacturing process according to claim 8, characterized in that: The sacrificial layer (2) is a polyimide layer.

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